Resmed's Central Sleep Apnea Detection - Resmed publication

JohnBFisher wrote:They also use the EEG leads to determine a central apnea. If there is no breating for 10 seconds and no effort during that time (as determined by the belts) *AND* as determined by the EEG leads the patient is not in a transition to or from sleep, then it is determined to be a central sleep apnea.

I agree that EEG can help determine whether a central is significant for a particular patient (by determining whether the central is a sleep-onset central, for example) but the event is technically a central either way, as I understand it. In fact, for some patients, repetitive sleep-onset centrals can be particularly significant as a factor in sleep-initiation insomnia, from what I've read. In other words, instability at transitions can, in and of itself, be pathological, for some patients, I believe. I agree that for most of us, occasional sleep-onset centrals or stage-transition centrals are perfectly harmless. But they are centrals nonetheless. At least to some docs, depending on what they are looking for with a particular patient.

I could have that all wrong though. I hope NotMuffy or -SWS or someone would correct me if I got that wrong, whether I liked it or not.

Oops. Sorry, John; I realize now I was preaching to the choir:

viewtopic.php?p=457468#p457468

jnk wrote:... In fact, for some patients, repetitive sleep-onset centrals can be particularly significant as a factor in sleep-initiation insomnia, from what I've read. In other words, instability at transitions can, in and of itself, be pathological, for some patients, I believe. I agree that for most of us, occasional sleep-onset centrals or stage-transition centrals are perfectly harmless. But they are centrals nonetheless. ...

Oops. Sorry, John; I realize now I was preaching to the choir:
viewtopic.php?p=457468#p457468

Yup! More like the choir conductor than a choir member.

In fact, besides a higher than normal tendency toward centrals throughout the night, I am VERY aware of sleep-onset central apneas. It DEFINITELY causes problems with me attaining sleep. Unfortunately for me, those sleep-onset central apneas are not short term. They often last a minute or more, causing severe desaturation of O2. I would suddenly awaken, gasping for air. Adrenaline rush, panic of fight or flight. It would happen over and over and over. I would end up with HORRIBLE headaches and dread trying to sleep.

I know all too well that this can be an issue. Even without the sleep-onset central apneas I would qualify for the ASV unit therapy. But if it did not handle the sleep-onset centrals, I would still be in a world of hurt.

So, while most PSG test do not score sleep-onset centrals, they are most definitely central apneas. And if they are frequent and/or profound enough, they should be treated just as any other apnea. But you are right. not every doctor realizes that these may require treatment.

linagee wrote:

. . . The 1 cm H2O amplitude pulses are able to be perceived by a patient if they are awake but are not large enough to arouse them from sleep. . . .

Ever? With any patient? Not even arousing some patients from one stage to another? Really? I wonder how they proved that? Well, they said it, so it must be true. They did say "arouse them from sleep," not 'cause arousals during sleep.'


If you think 1 cmH2O oscillation during apneas is bad, try using Respironics. 1.5 cmH2O increase/decrease *EVERY* three minutes. (Apneas or not.)

As a hypersensitive person whose been dealing with a nasty ever present tickle in the back of my throat caused by CPAP/APAP/BiPAP that's been driving me nuts off and on for 3 months now first on an S9 AutoSet (both in straight CPAP and Auto modes) and now on a PR BiPAP Auto running in straight BiPAP), I just gotta throw my $0.02 in here.

I strongly suspect, but cannot prove that those (unanticipated and unexpected) 1 cm H20 amplitude pulses on the S9 may well have at been arousing me at times---at least from one stage of sleep to another or from stage 1 to wake. But I don't sleep with an EEG, alas.

And I NEVER, EVER will be even TEMPTED to switch my PR BiPAP Auto from its current FIXED BiPAP mode to Auto BiPAP exactly BECAUSE of the fact that PR uses those constant 1.5 cm H20 increases/decreases every three minutes according to their literature as a way of maximizing the time spent at the minimally optimal pressure. I understand the mathematics behind the algorithm. I understand that there's a belief that "most people" are not going to be sensitive enough to notice this change in pressure---particularly when they are sound asleep. But there are a few of us with hypersensitive nervous systems that will and I'm pretty sure I'm one of them.

Now don't get me wrong: I know there's a pressure change everytime I inhale and exhale with my BiPAP. The difference is that those increases and decreases in pressure are largely controlled by me through my breathing, and hence my body (and the back of my throat) can and does anticipate them in a way that feels more "natural" (to me) than the ResMed's EPR algorithm ever did: The S9 with EPR somehow always managed to mess up the increase in pressure back up to the set CPAP/APAP pressure and made me feel like I was being forced to breath in before I was ready to and forced to breath in more air than I wanted to breath in as well. Hence I dreamed more than once of being a goose being fattend up for foie gras while sleeping with the S9.

Comparing an auto PAP to a bi-level auto is comparing apples and oranges, regardless the brand.